Wave pools have become popular at water theme parks in recent years. Wave pools are man-made bodies of water in which waves are created much like waves in an ocean. A wave pool typically has a wave generating machine located at one end and an artificial sloped “beach” located at the other end, wherein the wave generating machine creates non-standing waves, such as periodic waves, that travel from that end to the other end. The floor of the pool near the beach end is preferably sloped upward so that as the waves approach, the sloped floor causes the waves to “break” onto the beach.
In some cases, the size and power of wave pools have been increased so that they can intermittently serve as “cross-over” wave pools capable of producing larger surfing class waves that enable special surfing events and demonstrations to be conducted, such as those involving stand-up surfing maneuvers on state-of-the-art finned surfboards. These cross-over pools, as they are so called (i.e., they serve on one hand traditional swimmer/inner-tube floaters in a choppy basin of bobbing water, and on the other hand, surfers desiring larger progressive waves that break obliquely along the beach) are typically larger and have deeper floors than conventional water theme park wave pools. The object has been, in such case, to produce larger surfing class waves to accommodate the occasional expert surfer, while at the same time, producing modest waves for the majority of the mass market bobbing inner-tube floaters and swimmers.
Such cross-over wave pools, however, have several disadvantages. First, due to the increase in the size of the waves, there is the concomitant increase in the occurrence of rip currents which can reduce the “surfable” quality of the waves, and consequently, make it more difficult for participants to perform surfing maneuvers thereon. They can also increase the attendant risks. Rip currents are often created by the water level gradients that can occur in the along-shore direction of the pool, such as in the case of a pool with an obliquely oriented sloped floor, wherein as water builds up on one side of the pool, a reverse flow of water that travels against the movement of the oncoming waves can be created down the sloped beach, i.e., as water seeks its own equilibrium. These “rip currents” tend to flow against the oncoming waves and can detrimentally affect how water and wave energy dissipate. They can also cause waves to break sooner and less dramatically, in which case, there can be more white water and mass transport of water onto the beach. The waves can also break up into sections.
A second related disadvantage of the cross-over wave pool is that wave reflections that are similar to those that exist in nature can occur. For example, wave reflections typically occur when there is an end wall at the far end of the pool, or a relatively steep beach or reef, that tends to reflect the wave energy back across the wave pool in a reverse direction, such that, as the waves progress and are reflected back, they can interfere with the next oncoming wave. On account of such reflections, a backwash can be created, which can lead to a significant decrease in surfable wave quality, which in turn, can make performing surfing maneuvers more difficult
A third corollary disadvantage related to the formation of rip currents and wave reflections is the resultant reduction in the pool's productive asset value that can result from having to reduce the frequency of the waves in an attempt to reduce these unwanted movements and characteristics. Although it is usually desirable to increase the frequency of wave generation to increase the number of riders that can ride on the waves per hour (with a corresponding increase in revenue per hour using the same asset base), the downside to doing so is that the occurrence of rip currents and wave reflections can thereby increase. For example, it has been found that if surfable size waves (1.5 meter or higher) are generated every fifteen seconds or so, the likelihood is high that significant rip currents will then be created, and accordingly, when larger waves suitable for surfing are generated, it is often necessary to reduce the frequency of the waves to reduce the likelihood that these unwanted rip currents and wave reflections will occur. Therefore, an associated disadvantage that can result from the use of large cross over wave pools is that the frequency of wave generation can be reduced, i.e., such as down to one wave every minute to ninety seconds or more, in which case, the asset value of the property is reduced as well.
A fourth disadvantage is that such cross over wave pools tend to be larger and inherently more expensive to build. This is especially true when wave pools are installed in areas where land is scarce, and therefore, building larger cross-over wave pools, simply to increase wave size is not often very cost effective. Renovating an existing wave pool to make it larger also requires a significant amount of effort and expense.
A fifth disadvantage to the cross-over wave pool occurs in situations where wave pools are used to host surfing exhibitions and competitions. As discussed, because of the risks associated with making surfing waves bigger, some effort has been made to build cross-over wave pools that are sufficiently large enough to ‘dilute’ the rip current and wave reflection problems discussed above. For example, one way to make wave pools less reflective and reduce the occurrence of rip currents is to decrease the slope of the pool floor, which in turn, requires that the distance between where the waves break and the far end of the beach where the spectators are seated will have to be increased. Unfortunately, such a solution has the detrimental effect of forcing spectators (who are normally seated on bleachers or grandstands immediately behind the beach and above the waterline) further away from the waves, which can make it more difficult for them to see and enjoy the wave and surf action.
What is needed, therefore, is an improved and dedicated cross over surf pool design that enables larger and more frequent quality waves to be produced in a safe manner, without having to increase wave pool size, while at the same time, enabling the wave breaking characteristics to be controlled, and rip currents and wave reflections to be reduced, which would otherwise be detrimental to the formation of surfable waves.